Abstract

The high intensity spallation neutron source ESS is well set to start construction in 2013 and to deliver�rst neutrons in 2019. The project itself has been 20 years in gestation but there has been a determinationamongst the user community and those working in national and international neutron laboratories in Europethat it would be built. That determination is what has brought the project in where it is today. The baselinespeci�cation is for a 5 MW power, long pulse facility delivering neutrons to 22 independent instruments forthe study of materials in all their diversity from pharmaceuticals and membranes, to colloids and polymers, tomagnetic and superconducting materials, and on to engineering and archeological artefacts. The user communityis rich and equally diverse, containing approximately 6000 individuals according to �gures produced by ENSA,the European Neutron Scattering Association.This Conceptual Design Report represents the work of about 250 individual scientists and engineers aroundEurope and the rest of the world, with about 100 of them located in the central team in Lund in southernScandinavia where the facility is to be built, with Sweden and Denmark as co-hosts. As this team has grownover the past 2 years, the work intensity and output has risen considerably. It has taken some time for therealisation that ESS is �nally to be built, to be fully digested, but it is clear now that this is indeed accepted.The CDR is a technical document. It does not address organisational matters, nor governance matters andless so �nancial matters, although it must be emphasised that these subjects are borne in mind in arriving atthe scope of ESS and hence the speci�cation of the facility.Over the next 12 months, work will be engaged upon which will result in a Technical Design Report beingproduced together with a series of other documents such as an updated Costing Report. These documents willdemonstrate the sound foundation upon which the project is to be constructed and are a necessary, but notsu�cient, achievement to lead on seamlessly to construction. Su�ciency would require our 17 partner countriesto reach a political and �nancial agreement. We are con�dent that it is within their capabilities and resourcesto do so, and we look to them for such a signal.